Repositório RCAAP

The present work reports the occurrence of fungi on crops of economic importance in the region of Uberlândia, Alto Paranaíba and some cities of Goiás, by the analysis of reports generated by Laboratório de Micologia e Proteção de Plantas (LAMIP), Universidade Federal de Uberlândia, on samples of seeds or plant parts, from the year 2001 to 2008. The reports analyzed were classified by crop and, subsequently, notes were taken on the pathogens that were reported, on the type of analysis performed and on the amount of reports analyzed per crop. Two thousand four hundred ninety eigtht reports on samples of cotton, brachiaria, coffee, bean, maize and soybean were analyzed. Thirty six genera of fungi were found, and Deuteromycetes was the main cause of diseases, counting 82% of all occurrences. The main causal agent was Fusarium sp., which was responsible for 956 occurrences (18%), followed by Cladosporium sp. (682 occurrences, 13%) and Cercospora sp. (502 occurrences, 9%). Among the crops studied, soybean presented the largest amount of reports, 2071 (82% of all reports), followed by maize (127 reports, 5%), and bean (125 reports, 5%). Among the methods performed in LAMIP, the seed sanity test is the most required, followed by visual analysis and, last, the isolation.

The objective of this work was to evaluate the influence of the fruit maturation stage in the physical attributes and germination of Schefflera morototoni pyrenes subjected to pre-germination treatments. Fruits with green and purplish green coloration were collected from 14 individuals, pulped in running water, the hollow pyrenes were discarded after counting, together with those presenting retracted and oxidized endosperm, using the uniforms (with the greenish endosperm occupying the whole cavity of the pyrene). The experiment was conducted in completely randomized design in a 2 x 5 factorial (stages of fruit maturation and pre-germination treatments), with four repetitions in plots containing 25 pyrenes. For greater capacity and germination speed of the pyrenes, fruits should be harvested when they present a purplish green coloration, discarding those with hollow pyrenes, with retracted or oxidized endosperm. The germination capacity of the pyrenes with uniform endosperm varied between 50 and 60%, with the beginning of the process at about 40 days after sowing and extending for up to 60 days in vermiculite. Pulped pyrenes, dried and soaked in water at 60ºC for 5 minutes, followed by soaking in water at room temperature for 12 hours begin the germination process in less time, in relation to those pulped, dried, scarified and soaked for 6 hours. The fruit endocarp is permeable and rigid; however, it presents a natural opening when soaked. The objective was to evaluate the variability in seedling emergence measures of Schefflera morototoni from pyrenes of different individuals. Fruits of 14 individuals were pulped and pyrenes with uniform endosperm were selected. The experiment was conducted in completely randomized design with 14 treatments (individuals) and 11 repetitions in parcels containing 50 pyrenes with uniform endosperm treated by immersion in water at 60 ºC for 5 minutes and then soaked at room temperature for 12 hours. The substrate used was a mixture in proportion 2:1:1:1/2 (v/v) soil, commercial substrate Bioplant®, coarse sand and vermicompost, with pyrenes sown at 1 cm depth in expanded polystyrene trays, maintained in a nursery with 50% reduction in luminosity at average temperatures of 19.3ºC minimum and 30.2 ºC maximum and daily irrigation. Daily counting of seedlings evaluated capacity, time, rate, uniformity and synchrony of emergence, besides the distribution of frequency of emergence in relation to time. The emergence of seedlings is slow, irregular and asynchronous, taking more than 80 days for stabilization of the emergence. The percentage of seedlings can reach up to 57%, but even when the endosperm occupies the whole cavity of the pyrene and is greenish, the emergence of seedlings may not occur. There is variability in seedling emergence measurements from pyrenes of different Schefflera morototoni individuals.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Phytosanitary problems, among other factors, are the main cause of low productivity in the common beans crop. The presence of nematodes in the crop is a direct cause of low yield. The reproduction of the nematodes Heterodera glycines race 3, Melodogyne incognita, M. javanica and Pratylenchus brachyurus was evaluated in eleven bean cultivars under greenhouse conditions. A completely randomized design with six replicates was used in this study. Ten days after sowing, seedlings were transplanted and inoculated with 4000, 5000, 2000 and 110 eggs/seedling, with H. glycines, M. incognita, M. javanica and P. brachyurus, respectively. Evaluation occurred 35, 60, 60, and 45 days for the nematodes, in the sequence previously presented. The number of H. glycines females in the root system was counted and the cultivars presented values ranging from 2.50 ( Diamante Negro ) to 15.17 ( Emgopa 201-Ouro ). The soybean cultivar Conquista , used as control, presented 30.50 females per root system, differing significantly from the other bean cultivars. Only the cultivars Diamante Negro , FT-Nobre , and Iapar-80 , showed reproduction factors above 1.0 for Meloidogyne javanica. The tomato plant Santa Clara, also used as control, presented reproduction factor (RF) of 9.85. All bean cultivars were considered bad hosts for M. incognita, with RFs smaller than 1.0. The Santa Clara tomato presented RF of 6.18. Pratylenchus brachyurus presented reproduction factors near zero for all bean cultivars as well as for the control treatments tomato Santa Clara and maize 30F33. The low multiplication rates of the phytonematodes found in this study, in comparison with literature results of similar plants, could be explained by the inoculum source for the two Meloidogyne species and by the low level of inoculum used for Pratylenchus brachyurus.

Basil is mostly grown, in Brazil, by small farmers to sell the leaves. Climate factors play an important role on the development of medicinal, aromatic and condiment plants and on the production of active ingredients. This study analyzed the production of biomass and essential oil of basil (Ocimum basilicum L.) grown in different seasons, growth environments and fertilizations in Uberlândia, MG. Two experiments were done, the first one from September to October 2008 (season 1) and the second one from February to May 2009 (season 2). The experimental design was completely randomized, as a 2 x 2 factorial, two growth environments (protected environment and field) and two fertilization types (mineral and organic), and five repetitions. The planting space was 60 cm between rows and 30 cm between plants. Harvest was done on November 19 2008 and on May 20 2009.The variables analyzed were plant height, leaf length and width, fresh and dry matter mass, essential oil yield and composition. Plant height was greater on season 2, with average of 58.3 cm comparing the two seasons and growth environments. Significant interaction was found between season and growth environment for the variables plant height, fresh leaf mass and essential oil yield of dry leaves. Basil grown in the months of February to May 2009, in protected environment, favored culture development, production and essential oil yield.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Pesticide spray technology aims the uniform deposition of products in the target, with minimal losses to se soil or drift, which may have consequences in agricultural areas. In this context, the herbicide 2,4-D Amina represents a product with great environmental concern, but still widely used in modern agriculture. Thus, to obtain greater infesting plants control during desiccation, this study evaluated the spray process for the herbicide 2,4-D Amina, with the use of different spray nozzles and volumes, in relation to pesticide deposition, losses to the soil, drift and weed control. The field experiment was done at the research station of Syngenta Seeds Ltd., located in Uberlândia-MG, and the laboratory analyses were done at the Laboratório de Análise de Água do Instituto de Química and at the Laboratório de Mecanização Agrícola do Instituto de Ciências Agrárias, both of Universidade Federal de Uberlândia. The experimental design was randomized blocks with six treatments and four replications, in a total of 24 plots, as a 3x2 factorial: three spray nozzles (drift guard twin flat fan, turbo flat fan and air induction turbo flat fan) and two spray volumes (80 L ha-1 and 130 L ha- 1). Each esperimental unit was 35 m2 (7 x 5 m). The active ingredient used was 2,4-D Amina (at 806 g a.i. L-1) at the dose 1 L c.p. ha-1. A tracer, made of Brilliant Blue food dye (internationally registered by the Food, Drug & Cosmetic as FD&C Blue n.1), at 300 g ha-1, was added to the spray mixture. The spray process was studied by the deposition on the weeds, losses to the soil, and losses by exodrift. Also, the control of weeds on the area was studied. The deposition study, drift and losses to the soil was done by two distinct methods, to determine the relation and agreement between them: direct analysis of the active ingredient 2,4-D Amina, by liquid chromatography (HPLC), and the analysis by quantification of the tracer added to the mixture, using spectrophotometry. According to the results of the experiment, it can be concluded that the spray volume of 80 L ha-1 can be used for weed desiccation with the herbicide 2,4-D Amina, without compromising target coverage; air induction turbo flat fan nozzles promoted greater herbicide loss to the soil; the different nozzles used, with medium, coarse, and very coarse droplets, as well as the spray volumes 80 L ha-1 and 130 L ha-1, did not affect weed control; and the results of the deposition study and losses to the soil, obtained by liquid chromatography were not similar to those obtained by spectrophotometry.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

The chicken meat productive chain in Brazil has shown itself as an interesting competitive subsidy, considering the exporting capacity and the differentiation of market products. Nevertheless, intersectorial relations in this system can be considered contradictory, and in some ways even conflictive. Regarding this, one has pursued to evaluate the price transmission of aviary production from 1997 to 2008, through the analysis (in R$) of products price series, upstream: corn grain (kg), initial concentrate (kg), chick cutting (unit); farming culture: living chicken in Minas Gerais; downstream: wholesale and retail prices of full chicken, wholesale price of pork and bovine meat, retail price of chicken s thigh and chest; and indicators (PIB and IPCA). The econometric procedures applied were the Augmented Dickey-Fuller Test, estimation of VAR Model, Response to Impulse function, Variance Decomposition, and Granger Causality Test. The results have allowed to state that, in causality relations upstream of the agriculture and livestock activity, that between the living chicken s price and the chick cuttings price, is significant in both directions, according to the F test. In the downstream relations, it s been observed intense causality relations and price transmission between the industrialized products, as much in wholesale as retail spheres, including the substitutes (pork and bovine meat). Only full chicken retail has caused significant price variations for producers in Minas Gerais. The positive variations in internal income also cause positive variations in full chicken s price and chest cuttings for retail. The forecast for dataset suggests that living chicken s price in Minas Gerais seems to interfere in the other variables. Yet, there are signs of transmition at the direction of markets (wholesale and retail), and, by the contrary, low capacity of reversion (towards the producer). Thus, the input-product relations among the aviary activity of Minas Gerais and the agribusiness processes ate established in the direction of processing and distribution industry.

This study evaluated the effect of Pratlenchus brachyurus and Fusarium verticillioides, and their relationship, on growth and development of two mayze hybrids (30F80 and 30K73). The experiment was conducted in greenhouse conditions at Pioneer Hi-bred Research Center in Itumbiara, GO, Brazil. The experimental design was randomized blocks with 15 treatments and 10 replications. Treatments included a non-inoculated control; inoculation of Fusarium in the seed and in the soil; three populations levels of Pratylenchus at sowing and at 30 days after planting (50, 100 and 500 nematodes/plot), with and without the inoculation of Fusarium in the soil; and three populations leves of Pratylenchus inoculated 30 days after sowing with Fusarium inoculated in seed at sowing. At plant maturity the following variables were evaluated: plant height and ear length, stalk diameter, root fresh and dry matter, stalk fresh and dry matter, reproduction factor and fusariosis severity on the stalk. Fusarium stalk colonization was evaluated in a scale from 1 to 9. The 30F80 hybrid had lower plant height and ear length, stalk diameter, stalk and root fresh matter when the seeds were inoculated with the suspension of Fusarium and sowing immediately after inoculation. The maize hybrids 30F80 and 30K73, showed the lowest root length, stalk fresh and dry matter, and root fresh and dry matter mainly when the soil was inoculated with Fusarium and sown in the same day, and the inoculation with 500 juveniles and/or adults of Pratylenchus, was done 30 days after sowing. The maize hybrid 30K73 obtained lower plant height and ear length when seeds were inoculated with the suspension of Fusarium and sown in the same day. Maize seeds inoculated with Fusarium verticillioides at planting decreased plant height, ear length, and root and shoot fresh weight on both hybrids. Stalk diameter of 30K73 hybrid and root length of hybrid 30K73 were also reduced. Soil inoculation of Fusarium verticillioides at planting and Pratylenchus brachyurus inoculated 30 days after planting (500 nematodes/plot) decreased root elongation and stalk, and root dry weights on both hybrids. However, plant height was only reduced on 30K73 hybrid. Future research is needed to better understand the relationship between Pratylenchus brachyurus and Fusarium verticillioides on maize growth and development.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

The processes of smelting pig iron and steel produce large amount of slags and other wastes. These slags can be used in agriculture to correct soil acidity and/or as a source of silicon (Si), an element considered beneficial to plants. This study evaluated the effect of siderurgical slag Holcim on the sugar cane crop, compared to the certified slag Agrosilício® by parameters related to yield, industrial quality of the sugar cane and plant resistance to diseases and stem borer. Thus, a field experiment in Guaira Sugar Mill, Guaira-SP was done. The sugarcane variety SP80-3280 was grown in soil with three increasing doses of either Si source (400, 800 or 1600 kg ha-1) and a control treatment without application of any of the sources, in a randomized block design as a 2x3+1 factorial, resulting in seven treatments with four replications. Evaluations of plant tillers were done at 30, 60 and 90 days after planting and those of stem length were done 120 days after planting and at harvest. Analysis of leaf Si was done in samples collected 180 and 240 days after planting. Disease severity and the intensity of stem borer (Diatraea saccharalis) damage were done at harvest (after one year). It was observed that in the soil layer of 00-15 cm, Si concentration increased until the dose of 800 kg ha-1 of Holcin slag, while no effect was observed for either source in the other soil layers analyzed. The same effect was observed for leaf Si concentration, which remained unchanged with the application of either Si source to the soil. In contrast, the resistance of plants to diseases and to the stem borer increased when either source was applied up the dose of 800 kg ha-1 slag. The same dose effect was observed for yield. Although biometric parameters such as purity and fiber content of the juice were not affected by the silicate levels, POL and Brix of the juice were favorably affected by greater silicate doses, and at 1600 kg ha-1 Source 1 was better than Source 2. The use of slag dosed did not affect ATR (Total recoverable sugar); however, Source 1 was better than Source 2. The observed results show that similarly to Agrosilício® (Source 2), Holcim slag (Source 1) has high potential to be used in the cultivation of sugarcane, performing, for some variables, even better than the already certified Si source.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Universidade Federal de Uberlândia

Fundação de Amparo a Pesquisa do Estado de São Paulo

Genetically modified soybean, tolerant to glyphosate, expanded its growing area in few years becoming the most sown in the country. The advantages of its use are many compared to the conventional soybean, which has led soybean farmers to prefer it. However, since some markets still prefer conventional soybean and its production occurs in smaller areas, there is the need to supply the market with high genetic quality seeds. The contamination of conventional seed lots with transgenic seeds has occurred with high frequency, in many stages of the production chain. One of the possibilities is the contamination by natural crossing between conventional plants and transgenic ones, in seed production fields. Therefore, this study evaluated the efficacy of the use of isolation barriers with soybean and maize plants, as well as gene flow of a transgenic cultivar to a conventional one, in summer and winter crops. The cultivars used were conventional MG/BR 46 [Conquista] and transgenic BRS Valiosa RR. The field experiments consisted of the combination of the use of two kinds of physical isolation (soybeans or maize) with two sowing dates (summer and winter), in a total of four experiments. The summer experiments were done at Getúlio Vargas Experimental Farm, of EPAMIG, in Uberaba, MG, and the winter ones at Suçuarana Farm, in São Romão, MG. The field trials were characterized by sowing a 6.5-m-sided square with the transgenic cultivar, isolated on all sides by 3 m cultivated with maize plants or the conventional soybean, and sided by 8 m of conventional soybeans. The experimental unit consisted of a 6.5 m long row of the conventional cultivar, at distances of 0.5, 1, 2, 4, 6 and 8 meters, counted from the last isolation line. The seeds were harvested, and 200 g of each experimental unit were used for transgenic soybean detection bioassay at the Laboratório de Ensino de Sementes of ICIAG, UFU, while the remainder was sown in the field. Before flowering, the plants were desiccated with Roundup (Glyphosate 3 L ha-1). The surviving transgenic plants were counted and their frequency calculated. For the bioassay, the seeds were pre-soaked in a glyphosate solution (0.6% e.a.) for 16 hours before the germination test and evaluated on the 5th day, determining the frequency of normal and abnormal seedlings. It was concluded that: a) the frequency of transgenic plants was greater in winter sowings than in the summer, regardless of the barrier used; b) the gene flow was reduced with increase distance in all of the experiments; c) the 11 m distance was not sufficient to avoid gene flow, and, d) the bioassay was not effective in quantifying the gene flow.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior